Study of Graphite/Epoxy Composites for Material Flaw Criticality.

Descriptive Note:

Final rept. 18 May 79-31 Oct 80,

Corporate Author:

MATERIALS SCIENCES CORP BLUE BELL PA

Personal Author(s):

Report Date:

1980-11-01

Pagination or Media Count:

146.0

Abstract:

Usefulness of NDE methodology for assessing criticality of disbonds with two-dimensional planforms located in laminated graphiteepoxy composites has been examined. Linear elastic fracture mechanics approach, semi-empirical growth laws and methods of stress analysis based on a modified laminated plate theory have been studied for assessing growth rates of disbonds in a transverse shear environment. Elastic stability analysis has been utilized for laminates with disbonds subjected to in-plane compression andor shear. Results of nondestructive inspections and destructive tests have been correlated with analytical predictions. In addition, effects of moisture conditioning and cyclic loading on wave velocities and attenuation of sound in graphite epoxy composites and in neat resin samples have been studied. Author